It'd be kinda strange for both parking lights to fail in tandem. I'd check the power wiring (should be green wires leading out from the 10A Tail (yes - taillight) fuse.

I also notice on the wiring diagram that both parking lights ground to the same point (somewhere on the front left fender).

Are your front turn signals working? The reason I mention this is because (according to that generation's wiring diagram) the front signals also ground to the same place. If all parking / signal lamps are dead I'd take that as a clue to a probably grounding issue. Just my .02 ...